Muscle heating effects

As an ingredient in medicines, capsaicin is used to relieve pain from arthritis, muscle aches, and sprains. It is a rubefacient, meaning it dilates blood vessels. The heat effect overwhelms nerves, causing a localized numbing sensation. 

Heat effects are certainly related to current density in volume conductors, but this is not necessarily so for nerve and muscle excitation. Excitation under a plate electrode on the skin is more highly correlated to current than current density (see Section 10.16.1). The stimulus summation in the nerve system may reduce the current density dependence if the same current is spread out over a larger volume of the same organ. Therefore, and for practical reasons, safe and hazard levels are more often quoted as current, energy or quantity of current in the external circuit, and not current density in the tissue concerned. 

The consequences of contact with electricity are electric shock, where the injury results from the flow of electricity through the body s nerves, muscles and organs and causes abnormal function to occur (the heart stops, for example) electrical burns resulting from the heating effect of the current which burns body tissue and electrical fires caused by overheating or arcing apparatus in contact with a fuel. 

The effect of therapy was a significant increase in haemoglobin level of 42% (mean), rising from the very low value of 76 to 102 g dm. Pre-treatment skeletal muscle heat production rate was lower than normal, 0.36 mW g ... 

Heats of solution are the basis for instant cold packs and instant hot packs used for the first-aid treatment of minor sprains and pulled muscles. These packs have two separate compartments. One contains water, and the other contains a salt NH4 NO3 for cold packs and MgSO. or CaCl2 for hot packs. Kneading the pack breaks the wall between the compartments, allowing the salt to mix with water. As the salt dissolves to form an aqueous solution, the temperature of the pack changes. Heat is absorbed or released only as the salt dissolves, however, so after all of the salt has dissolved, the pack gradually returns to room temperature. Further manipulation of the pack has no effect. 

Resistance in the arterioles of the working muscles is regulated locally. As discussed previously, active hyperemia results in production of several factors that cause metabolic vasodilation. Exercising muscles generate COz, H+ and K+ ions, heat, and adenosine. The vasodilator effect of these locally produced substances overrides the vasoconstrictor effect of the sympathetic system in the muscle. As a result, local vascular resistance is decreased. The combination of increased driving pressure and decreased local vascular resistance causes an increase in blood flow to the working muscles. 

Lynn et al. [71] demonstrated the damaging effect of arsenite on DNA. It has been shown that arsenite at low concentrations increased DNA oxidative damage in vascular smooth muscle cells (VSMCs) that can be a cause of arsenite-induced atherosclerosis. Bruskov et al. [72] found that heat induced the formation of 8-oxoguanine in DNA solution at pH 6.8, which was supposedly mediated by oxygen radicals. 

Adverse effects are usually due to excessive doses (which may occur if the initial increase in metabolism is too rapid) and correspond to symptoms of hyperthyroidism, but they usually disappear after dose reduction or withdrawal of treatment. The most common adverse effects affect the following system as Heart arrhythmias, anginal pain, Central nervous system headache, hyperactivity, sweating, tremor, heat intolerance, Gastrointestinal tract diarrhoea, excessive weight loss, vomiting, Musculoskeletal system muscle cramps, muscle weakness. 

Bai Shao Yao is bitter, sour and slightly cold, and enters the Liver and Spleen meridians. It is able to nourish the Yin and therefore soften the liver. In addition, it can reduce the empty-heat from the Liver, which is often caused by Yin deficiency. Thus it is considered an effective herb to soften and pacify the liver, and is used to treat cramping pain due to Yin deficiency that fails to nourish the tendons and muscles. It is also selected in emotional disturbances such as stress, anger, frustration, resentment and irritability. 

Bai Shao Yao is sour, bitter and cold, and enters the Liver and Spleen meridians. Tian Men Dong and Sheng Di Huang are sweet, bitter and cold, and enter the Kidney meridian. These herbs can effectively nourish the Yin, reduce the heat and extinguish internal wind. In addition, as Bai Shao Yao can soften the Liver and ease tendons, it is a good choice when there is muscle cramp and convulsions. 

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